Make the CompositeMapRenderer use available time and add related setting

apps/openmw/mwgui/loadingscreen.cpp

@@ -163,7 +163,6 @@ namespace MWGui
         if (mViewer->getIncrementalCompileOperation())
         {
             mViewer->getIncrementalCompileOperation()->setMaximumNumOfObjectsToCompilePerFrame(100);
-            mViewer->getIncrementalCompileOperation()->setTargetFrameRate(getTargetFrameRate());
         }
 
         // Assign dummy bounding sphere callback to avoid the bounding sphere of the entire scene being recomputed after each frame of loading

apps/openmw/mwrender/renderingmanager.cpp

@@ -205,7 +205,10 @@ namespace MWRender
         mObjects.reset(new Objects(mResourceSystem, sceneRoot, mUnrefQueue.get()));
 
         if (getenv("OPENMW_DONT_PRECOMPILE") == NULL)
+        {
             mViewer->setIncrementalCompileOperation(new osgUtil::IncrementalCompileOperation);
+            mViewer->getIncrementalCompileOperation()->setTargetFrameRate(Settings::Manager::getFloat("target framerate", "Cells"));
+        }
 
         mResourceSystem->getSceneManager()->setIncrementalCompileOperation(mViewer->getIncrementalCompileOperation());
 
@@ -223,6 +226,7 @@ namespace MWRender
         else
             mTerrain.reset(new Terrain::TerrainGrid(sceneRoot, mRootNode, mResourceSystem, mTerrainStorage, Mask_Terrain, Mask_PreCompile));
         mTerrain->setDefaultViewer(mViewer->getCamera());
+        mTerrain->setTargetFrameRate(Settings::Manager::getFloat("target framerate", "Cells"));
 
         mCamera.reset(new Camera(mViewer->getCamera()));
 

components/terrain/compositemaprenderer.cpp

@@ -10,7 +10,8 @@ namespace Terrain
 {
 
 CompositeMapRenderer::CompositeMapRenderer()
-    : mTimeAvailable(0.0005)
+    : mTargetFrameRate(120)
+    , mMinimumTimeAvailable(0.0025)
 {
     setSupportsDisplayList(false);
     setCullingActive(false);
@@ -22,6 +23,14 @@ CompositeMapRenderer::CompositeMapRenderer()
 
 void CompositeMapRenderer::drawImplementation(osg::RenderInfo &renderInfo) const
 {
+    double dt = mTimer.time_s();
+    dt = std::min(dt, 0.2);
+    mTimer.setStartTick();
+    double targetFrameTime = 1.0/static_cast<double>(mTargetFrameRate);
+    double conservativeTimeRatio(0.75);
+    double availableTime = std::max((targetFrameTime - dt)*conservativeTimeRatio,
+                                    mMinimumTimeAvailable);
+
     mCompiled.clear();
 
     OpenThreads::ScopedLock<OpenThreads::Mutex> lock(mMutex);
@@ -39,7 +48,7 @@ void CompositeMapRenderer::drawImplementation(osg::RenderInfo &renderInfo) const
         mImmediateCompileSet.erase(mImmediateCompileSet.begin());
     }
 
-    double timeLeft = mTimeAvailable;
+    double timeLeft = availableTime;
 
     while (!mCompileSet.empty() && timeLeft > 0)
     {
@@ -126,9 +135,14 @@ void CompositeMapRenderer::compile(CompositeMap &compositeMap, osg::RenderInfo &
     ext->glBindFramebuffer(GL_FRAMEBUFFER_EXT, fboId);
 }
 
-void CompositeMapRenderer::setTimeAvailableForCompile(double time)
+void CompositeMapRenderer::setMinimumTimeAvailableForCompile(double time)
 {
-    mTimeAvailable = time;
+    mMinimumTimeAvailable = time;
+}
+
+void CompositeMapRenderer::setTargetFrameRate(float framerate)
+{
+    mTargetFrameRate = framerate;
 }
 
 void CompositeMapRenderer::addCompositeMap(CompositeMap* compositeMap, bool immediate)

components/terrain/compositemaprenderer.hpp

@@ -40,7 +40,10 @@ namespace Terrain
         void compile(CompositeMap& compositeMap, osg::RenderInfo& renderInfo, double* timeLeft) const;
 
         /// Set the available time in seconds for compiling (non-immediate) composite maps each frame
-        void setTimeAvailableForCompile(double time);
+        void setMinimumTimeAvailableForCompile(double time);
+
+        /// If current frame rate is higher than this, the extra time will be set aside to do more compiling
+        void setTargetFrameRate(float framerate);
 
         /// Add a composite map to be rendered
         void addCompositeMap(CompositeMap* map, bool immediate=false);
@@ -51,7 +54,9 @@ namespace Terrain
         unsigned int getCompileSetSize() const;
 
     private:
-        double mTimeAvailable;
+        float mTargetFrameRate;
+        double mMinimumTimeAvailable;
+        mutable osg::Timer mTimer;
 
         typedef std::set<osg::ref_ptr<CompositeMap> > CompileSet;
 

components/terrain/world.cpp

@@ -65,6 +65,11 @@ World::~World()
     delete mStorage;
 }
 
+void World::setTargetFrameRate(float rate)
+{
+    mCompositeMapRenderer->setTargetFrameRate(rate);
+}
+
 float World::getHeightAt(const osg::Vec3f &worldPos)
 {
     return mStorage->getHeightAt(worldPos);

components/terrain/world.hpp

@@ -57,6 +57,9 @@ namespace Terrain
         World(osg::Group* parent, osg::Group* compileRoot, Resource::ResourceSystem* resourceSystem, Storage* storage, int nodeMask, int preCompileMask);
         virtual ~World();
 
+        /// See CompositeMapRenderer::setTargetFrameRate
+        void setTargetFrameRate(float rate);
+
         /// Apply the scene manager's texture filtering settings to all cached textures.
         /// @note Thread safe.
         void updateTextureFiltering();

docs/source/reference/modding/settings/cells.rst

@@ -178,6 +178,14 @@ cache expiry delay
 The amount of time (in seconds) that a preloaded texture or object will stay in cache
 after it is no longer referenced or required, for example, when all cells containing this texture have been unloaded.
 
+target framerate
+----------------
+:Type:          floating point
+:Range:         >0
+:Default:       60
+
+Affects the time to be set aside each frame for graphics preloading operations. The game will distribute the preloading over several frames so as to not go under the specified framerate. For best results, set this value to the monitor's refresh rate. If you still experience stutters on turning around, you can try a lower value, although the framerate during loading will suffer a bit in that case.
+
 pointers cache size
 ------------------
 

files/settings-default.cfg

@@ -79,6 +79,9 @@ prediction time = 1
 # How long to keep models/textures/collision shapes in cache after they're no longer referenced/required (in seconds)
 cache expiry delay = 5
 
+# Affects the time to be set aside each frame for graphics preloading operations
+target framerate = 60
+
 # The count of pointers, that will be saved for a faster search by object ID.
 pointers cache size = 40